This error sometimes appears when the Zend Optimizer isn't correctly set in your php.ini. There is a quick and easy way to get this done. Please find the outlined steps below:

ERROR MESSAGE THAT YOU MAY SEE:

[29-Mar-2009 09:44:56] PHP Warning: Zend Optimizer for PHP 5.2.x cannot be found (expected at \'/usr/local/Zend/lib/Optimizer/php-5.2.x/ZendOptimizer.so\') - try reinstalling the Zend Optimizer in Unknown on line 0

How to find the location of your main php.ini file:

1. Create a phpinfo() page, and upload it into the /public_html/
2. Browse to this page using your internet browser
3. Towards the top of the phpinfo page, you will see "Loaded Configuration File"
4. Copy the location of the php.ini file such as this one: "/usr/local/lib/php.ini"

How to copy / paste a new php.ini file into your /public_html/

1. Login to SSH (this information can be found in your welcome email)
2. Navigate to your /public_html/ normally can be done with the below line:

   # cd /home/<cpanel-username>/public_html/

3. Now, you will need to copy and paste the below command (provided that the php.ini location is the same as in the above section:

   # cp /usr/local/lib/php.ini php.ini

4. Now, we will need to set the ownership of this file:

   # chown <cpanel-username>:<cpanel-username> php.ini

5. Well done, your php.ini has been copied to your /public_html/, this should fix the errors that you where experiencing.